To All,

I was performing a comparison check of the results from CAESAR II and Autodesk Inventor. But results are different. I changed the Yield Stress Criterion from the configuration editor but still results are different.

BTW, my piping is a straight pipe, anchored on both ends.

Are the assumed anchor stiffness values the same? Same piping code/load cases?

Yes, this is the case where the anchor stiffness makes a significant difference. Even if you don't manually define the stiffness in CAESAR II input, specifying rigid ANC or any rigid restraint would use CAESAR II default stiffness. See configuration editor>computational control>input spreadsheet defaults.

This is a very simple model.
Compare elastic modulus value at hot temperature and thermal expansion factor, pressure.
Check equations https://www.whatispiping.com/restrained-and-unrestrained1